1	Neuromuscular Fundamentals
2	Muscular Attachments 1. Origin 2. Insertion 3. Muscle pulls on both ends of the muscle with equal tension 4. One end of the muscle usually moves a bone, while the other end usually remains stable. 5. This varies, however with the type of movement 6. Sometimes the bone attached to the insertion is stable and the bone at the origin moves.
3	Classification of Muscles on the basis of fiber arrangement Longitudinal – long, straplike muscles whose fibers run parallel to its long axis; sartorius, rectus abdominis Quadrate – four sided and usually flat, consist of parallel fibers; pronator quadratus, rhomboid Triangular or fan-shaped; pectoralis major Fusiform or spindle-shaped; brachialis, brachioradialis
4	"5." 5. Unipenniform – featherlike fibers, short and parallel, extend diagonally from the side of a long tendon; extensor digitorum longus, rectus femoris 6. Multipenniform – several tendons are present, muscle fibers run diagonally between them; deltoid
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7	Effect of Muscle Structure on Force and Range of Motion The force a muscle can produce is proportional to its physiological cross-sectional area The range through which it shortens depends on the length of the fibers, with the average muscle fiber shortening about ½ of its resting length.
8	Skeletal Muscle Function Line of pull- the movement that the contracting muscle produces – flexion, extension, abduction, adduction, or rotation – is determined by two factors: the type of joint that it spans whose axes of rotation may be longitudinal, bilateral, or anterior-posterior. and the relation of the muscle’s line of pull to the joint; pectoralis major clavicular portion.
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10	Types of Muscle Action Isometric Concentric Dynamic Constant Eccentric Resistance Isokinetic Ballistic
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12	Force Production Motor Unit Recruitment Cross-sectional area: Physiological and anatomical Velocity of Shortening Angle of Pennation Sarcomere and Muscle Length Prestretching – Stretch-shortening Cycle
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17	Contractile Element
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21	Length-Tension Relationship
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23	Force-Velocity Relationship
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28	Stored Elastic Capabilities Stretch-shortening cycle – When a concentric contraction is preceded by a phase of active stretching, elastic energy is stored in the muscle and available for use in the contractile phase.
29	Influence of Gravity Upward against gravity Downward with gravity Horizontal, perpendicular to gravity, not influenced by gravity Muscles may provide a force to cause movement, or a force to resist movement, or may be relaxed. Muscle that raises the weight resists gravity to lower the weight Some movement may be caused by external forces.
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31	Roles of Muscles Agonists (prime movers)– directly responsible for producing a movement. Antagonists – have an effect opposite to the primer movers or muscles acting eccentrically to brake the movement of a limb
32	"Synergists – Muscles that assist..." Synergists – Muscles that assist in the action but are not necessarily prime movers for the action Stabilizers, fixator, and supporting muscles contract statically to steady or support some part of the body against the pull of the contracting muscles, against the pull of gravity, or against the effect of momentum and recoil in certain vigorous movements Neutralizers act to prevent an undesired action of one of the movers.
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35	"4." 4. Ballistic – movement started with great force and allowed to carry on by its own momentum 5. Cocontraction – simultaneous contraction of both agonists and antagonists; neutralizing, stabilizing
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37	Spurt and Shunt Muscles Spurt – where the distance from the stationary bone to the axis of rotation is long, as compared to its distance from the moving bone; biceps brachii
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39	"Shunt – where the distance..." Shunt – where the distance from its attachment to the moving bone is longer than its attachment to the stable bone; brachioradialis
40	Biarticular Muscles Rectus femoris: crosses hip and knee; hip flexion, knee extension
41	"Semitendinosis:" Semitendinosis: crosses hip and knee; hip extension, knee flexion
42	"Sartorius:" Sartorius: crosses hip and knee; hip flexion, knee flexion
43	"Biceps brachii," Biceps brachii, LH: crosses shoulder and elbow; shoulder and elbow flexion
44	Rotary and Stabilizing Components
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46	Proprioception Proprioceptors are specialized sensory receptors located within the muscles, tendons, and joints. These receptors are sensitive to tension and pressure and relay information back to the spinal cord; afferent fibers. Proprioceptors give information back to the CNS and provide a Kinesthetic sense. Most of this information is processed at subconscious levels.
47	Muscle Spindles Are parallel to the muscle fibers (extrafusal) and stretch when the muscles stretch and shorten when the muscles shorten It sends a signal back to the spinal cord via a Ia afferent neuron These receptors measure length and changes in length of the muscle fibers.
48	"4." 4. Within the muscle spindle are muscle fibers called intrafusal fibers that can adjust the length of the spindle to the conditions of the extrafusal muscle fibers. 5. The intrafusal muscle fiber of the spindle is innervated by a gamma efferent motor neuron
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50	Golgi Tendon Organs These receptors are located in the tendons, in series with the muscle fibers and measure tension and changes in tension. It sends a signal back to the spinal cord via a Ib sensory neuron.
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52	A Reflex Arc Illustrating Reciprocal Inhibition